Removable breaking calibration connector for toroidal conductivity sensor and method of calibration

Abstract

This invention relates to electrical connectors used with non-invasive toroidal conductivity sensors and calibration thereof. A removable breaking calibration connector is provided for temporary insertion in the electrical circuit to selectively break connection to a sense toroid for zero out calibration in situ while retaining connection to the drive toroid and other peripherals, even when process fluid is flowing in the pipes.

Description

RELATED APPLICATION DATA [0001]The present application claims benefit of 60 / 548,924 filed on Feb. 27, 2004.FIELD OF INVENTION[0002]The present invention relates generally to toroidal conductivity sensors and more particularly to connectors therefor, including removable breaking calibration connector portions for calibration thereof.BACKGROUND OF INVENTION[0003]Toroidal electrodeless conductivity (EC) sensors are used to measure conductivity in a process fluid by use of electromagnetic cores, i.e., toroids. At least two toroids are typically used, one being a ‘drive’ toroid and the other being a ‘sense’ toroid. The sensor unit applies current to the drive toroid, which in turn induces a current in the sense toroid, through a current induced in the process fluid. The current induced in the sense toroid is proportional to the conductivity of the process fluid passing through the process pipe and through the toroids.[0004]The toroidal conductivity sensors have been one of the industry s...

AI Technical Summary

Benefits of technology

The present invention provides a toroidal conductivity sensor assembly with a drive toroid and a sense toroid that can be placed in a process flow path. The sensor is controlled by an analyzer and connected to it through a multiple conductor cable. A calibration connector is included that can be used to temporarily disable the sensor for zero out calibration without emptying it of process fluid. The calibration connector has male and female interfaces that block electric signals between the analyzer and the sense toroid while passing them between the analyzer and the drive toroid. The invention also includes a method for calibrating the sensor by using the analyzer and the calibration connector. The connector allows for easy and efficient calibration of the toroidal conductivity sensor without shutting down the process.

Problems solved by technology

Until recently most of the toroidal sensors were invasive in nature, that is, the sensor protruded into the process flow.

However, in some applications the invasive nature of such toroidal EC sensors presents an undesirable impediment of the process flow.

This impediment may be particularly problematic in applications in which the process flow is relatively thick and / or viscous, which tend to generate buildup around the sensor, which in turn, may lead to erroneous conductivity measurements.

A drawback of this approach is that this installation is relatively labor intensive, and there is a possibility that such hand-wiring may be performed incorrectly.

In these situations, if the sensor is to be removed for replacement, often some or all of the wiring needs to be removed and then reinstalled, causing undesirable delays and costs associated with process down-time.

However, in order to calibrate the process for low-end conductivity and / or to zero out the sensor, the process pipe typically needs to be drained completely of any process fluid.

This may be relatively difficult and potentially hazardous, e.g., in the event the process fluid is caustic or otherwise aggressive.

In either case, such emptying or drying of the process pipe of the process fluid poses a problem to the user because it generally requires that the process be shut-down, thereby increasing the cost of production.

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